#include<iostream>
#include<cstring >
#include<cassert>
using namespace std;
void* my_memcpy(void* dest, const void* src, size_t num)
{
	void* ret = dest;
	assert(src && dest);
	while (num--)
	{
		*(char*)dest = *(char*)src;
		dest = (char*)dest + 1;
		src = (char*)src + 1;
	}


}
int main()
{
	int arr1[] = { 1,2,3,4,5,6,7,8,9,0 };
	my_memcpy(arr1 + 2, arr1, 21);
	int i = 0;
	for (i = 0; i < 10; i++)
	{
		cout << arr1[i];
	}




}